States of Matter – Chapter 2: Section 1
states of matter – the physical form that a substance exists
example: water – liquid (water), solid (ice), gas (steam)
matter – made up of particles called atoms and molecules
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Particles always moving
Particles of a solid
don’t move fast
solid – keeps original shape and volume
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Particles of a liquid
move little faster
Particles of a gas
far apart, moving
Particles close together
Attraction between particles stronger than other particles of same substance
Vibrate in place
Two kinds of solids
1. crystalline solids – orderly, three-dimensional arrangement, repeating pattern of rows
iron, diamond, ice
2. amorphous solid – do not have special arrangement, no pattern
glass, rubber, wax
liquid – definite volume, takes the shape of the container
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particles move fast enough to overcome some of the attraction
particles slide past each other
Liquids Have Unique Characteristics
1. surface tension – force that acts on the particles at the surface of a liquid
 spherical drop – like beads of water
 flat drop – like gasoline
2. viscosity – liquids resistance to flow
 the stronger the attraction between molecules the more viscous
 Example: honey is more viscous than water, honey flows slower than water
Gases – state of matter that has no definite shape or volume
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Particles can completely break away from each other
Less attraction between particles of the same substance
Amount of space between particles can change
Example: helium particles in a tank verses in a helium filled balloon
Behavior of Gases – Section 2
Gases
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have a large amount of space between them
the space that gas particles occupy is the gas’s volume
behavior of particles of gas depends on temperature and pressure
Temperature – measure of how fast the particles in an object are moving
- faster the particles are moving, the more energy they have
Example: Parade Balloon
Hot day
– particles of gas moving faster hitting inside walls of balloon harder
- gas is expanding and pushing on the inside walls with more force
Cool day
- particles of gas have less energy
- will not push as hard on the walls of the balloon
- need more gas to fill the balloon
Volume – the amount of space an object takes up
- Particles of gas can be compressed, or squeezed together into a smaller volume
- particles of liquid cannot compressed as much as particles of gas
Pressure – the amount of force exerted on a given area of surface (how many times the
particles of gas hit the inside of the container
Same size container: basketball verses beach ball
Basketball
high pressure – more particles of gas in the basketball, particles closer together,
particles collide with the inside of the ball at a faster rate
low pressure – beach ball has fewer particles of gas, farther apart, collide with other
particles in the beach ball slower
Gas Behavior Laws – temperature, pressure, and volume of gas are all linked
Gas Laws – the relationship between temperature, pressure, and volume
Boyle’s Law – relationship between the volume and pressure of a gas
- as the pressure of gas increases, the volume decreases by the same amount
(inversely related)
- as one goes up the other comes down
Charles’s Law – the volume of gas changes in the same way that the temperature of the
gas changes
- temperature increases, volume increases
- temperature decreases, volume decreases